interference

American  

[in-ter-feer-uhns] / ˌɪn tərˈfɪər əns /

noun

1. an act, fact, or instance of interfering.

2. something that interferes.

3. Physics. the process in which two or more light, sound, or electromagnetic waves of the same frequency combine to reinforce or cancel each other, the amplitude of the resulting wave being equal to the sum of the amplitudes of the combining waves.

4. Radio.

   1. a jumbling of radio signals, caused by the reception of undesired ones.

   2. the signals or device producing the incoherence.

5. Football.

   1. the act of a teammate or of teammates running ahead of a ball-carrier and blocking prospective tacklers out of the way.

      to run interference for the halfback.

   2. such a teammate or such teammates collectively.

      to follow one's interference.

   3. the act of illegally hindering an opponent from catching a forward pass or a kick.

6. Aeronautics. the situation that arises when the aerodynamic influence of one surface of an aircraft conflicts with the influence of another surface.

7. Linguistics.

   1. (in bilingualism and foreign-language learning) the overlapping of two languages.

   2. deviation from the norm of either language in such a situation.

8. the distorting or inhibiting effect of previously learned behavior on subsequent learning.

9. Psychology. the forgetting of information or an event due to inability to reconcile it with conflicting information obtained subsequently.

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idioms

1. run interference, to deal with troublesome or time-consuming matters, as for a colleague or supervisor, especially to forestall problems.

interference British  

/ ˌɪntəfəˈrɛnʃəl, ˌɪntəˈfɪərəns /

noun

1. the act or an instance of interfering

2. physics the process in which two or more coherent waves combine to form a resultant wave in which the displacement at any point is the vector sum of the displacements of the individual waves. If the individual waves converge the resultant is a system of fringes. Two waves of equal or nearly equal intensity moving in opposite directions combine to form a standing wave

3. Also called: radio interference.  any undesired signal that tends to interfere with the reception of radio waves

4. aeronautics the effect on the flow pattern around a body of objects in the vicinity

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interference Scientific  

/ ĭn′tər-fîr′əns /

1. The superposition of two or more waves propagating through a given region. Depending on how the peaks and troughs of the interacting waves coincide with each other, the resulting wave amplitude can be higher or smaller than the amplitudes of the individual waves.

2. ◆ When two waves interact so that they rise and fall together more than half the time, the amplitude of the resulting wave is greater than that of the larger wave. This is called constructive interference.

3. ◆ When two waves interact such that they rise and fall together less than half the time, the resulting amplitude is smaller than the amplitude of the stronger wave. This interference is called destructive interference. It is possible for two waves of the same magnitude to completely cancel out in destructive interference where their sum is always zero, that is, where their peaks and troughs are perfectly opposed.

4. See more at wave

5. In electronics, the distortion or interruption of one broadcast signal by others.

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interference Cultural  

1. The disturbance that results when two waves come together at a single point in space; the disturbance is the sum of the contribution of each wave. For example, if two crests of identical waves arrive together, the net disturbance will be twice as large as each incoming wave; if the crest of one wave arrives with the trough of another, there will be no disturbance at all.

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Discover More

One common example of interference is the appearance of dark bands when a light is viewed through a window screen.

Other Word Forms

• interferential adjective
• overinterference noun

Etymology

Origin of interference

First recorded in 1775–85; interfere + -ence

Explanation

Interference is something that is in your way. If the sound of your sister's band practicing keeps you from getting your homework done, that’s interference. Governments are sometimes accused of interference in other countries' affairs. If your neighbor’s in a civil war and your president sends in troops, your country may be accused of interference in that country's internal affairs, If all you hear on your radio is static, you’ve got interference — something is blocking the clear signal. And when a football player blocks another player, that's also interference. The Latin roots of interference are entre-, “between,” and ferire, “strike.”

Example Sentences

But that’s more an issue of capacity over top-down interference.

From Slate • Apr. 3, 2026

Even if they say they align and support you, be sure you have your own cash reserves, should you believe that the cost of their interference is not worth the gift.

From MarketWatch • Apr. 3, 2026

He will not tolerate interference and will not stand for players who won't do what he wants them to.

From BBC • Apr. 3, 2026

The results confirm that multiple optical links can operate at the same time without significant interference.

From Science Daily • Apr. 2, 2026

“Cadet Fitz’s interference is not why you did not earn your point,” she said.

From "Glitch" by Laura Martin

Related Words

• conflict
• intervention
• intrusion
• obstruction
• tampering